Apparatus for testing textiles and like materials



Aug. 31 1926. 1,598,141

J. E. G. LAHOUSSE- APPARATUS FOR TESTING TEXTILES AND LIKE MATERIALS Filed March 6, 1925 A TTo H NETS Patented Aun. 31. 1926.

UNITED STATES,

PATENT OFFICE.

JOSEPH EDOUARD GUSTAVE LAHOUSSE, OF TERNAY, FRANCE, ASSIGNOR T SOCIETE CHIMIQUEWDES USINES DU RHONE, OF RARIS,

APPARATUS FOR TESTING TEXTILES ANI) L'IKE MATERIALS.

' Application led March 6, 1925, Serial No. 13,605, andin Germanyllareh 4, 1924.

The present invention relates-to the process for testing textiles and like materials as described in my patent application No. 1,- 517,911, in which the grade of the textile is U ascertained byobserving the position of the nodes produced when said textile is caused.

to vibrate by means of a tuning fork, asdescribed in said patent specification. l

The object of this'invention is an apparatus adapted to permit'of the vibrations being maintained' electrically by alternating current using the electric supply from the ordinary lighting or power mains, while eliminating the errors due to possible variations in the frequency of sald supply.

According` to .this invention, I substitute' for the tuning fork a vibrating member of magnetic materia ,the vibrations being caused by a bobbin having a magnetic core, preferably laminated in the known manner (said bobbin being placed between the branches of the said vibratingmembervwhen 'the latter is forked), and being connected to the electric supply mains through the usual 95 switch, a suitable resistance being put in' i4purpose in view,.I have found that the frolcircuit if the bobbin has not been designed with a suliicient-resistance to suit the voltage of the supply.

It is known that if neither the tuning fork nor` the magnetic core is magnetized, the vibrating member must be tuned to a frequency which is double that of the supply; if, on the'contrary, the magnetic circuit is polarized, as is done in the case of telephonie receivers, the frequency of the vibrationsof the vibrating member is equal to that of the supply. Thepolarization of the magnetic circuit can be obtained either by magnetizing the vibrating member, considered as a horse-shoe magnet, and made of a suitable steel, or in providing it .witha supplementary bobbin, in. which `passes a continuous current, and located so as to utilize the magnetic circuit in an eilicient manner.

Among all the well-,known yelectric arrangements possible f or` carrying out the `quency* of Ath"vv l a little, a displacement ofY the'node of this vertical vibrating blade of magnetic material clamped at the upper end and" free at lthe other. This-armature is selected so that its period of free vibration is nearly double that of the supply. It is provided at its lower end with a small hole in which the thread to be tested iscausedto pass. This thread is fixed` in a clamping device located approximately on a vertical line passing through the hole and above the armature. At the bottom, thisthread supports a tight-v ening weight, as has been described inthe specification referred to above, and the"po sition of its nodes gives the measure of its grade or of itsnumber as is explained in said specication.

With an arrangement so constituted', va-

is provided; another similar arrangementv being set up at the side lof the arrangement described above, 'the armature of which sets .in vibration a line standard thread, 1

preferably metallic, kept taut by a known weight. l

This weight is naturally selected lso that c the comparison thread vibrates,l with at least one node','f with double the normal fre- "spply. If the latter varies thread takesjplace, from which displacement 'the correctionto be made to the indications of L the scale ofthe neighboring device carrying hal thread to be tested can be deduced as o ows:

Let H' be the distance of the node.. under consideration to the pointwhere the tight-4 ening weight is suspended to the comparison thread, ata' momentv when.. the supply 05 possesses exactly its normal frequency; .let I upon the correction l l v I l 'a be the increase of this distance due to the variation of fre uency of the supply; let d be, as in specication No. 1,517,911, the actual means of unit of length of the thread,` and let d be the observed value of this mass as read on the scale (graduated for the normal frequency of the supply) then, t,

according to the classical theory of vibrating strings d=w 1 f-I ,y rovided g be small,l which is always the P H divergencies of frequency of the case, since of the order of i3 to supplies are, in fact, 4% at the maximum, a being negative.

The above formula shows that the correct value d is deduced from the observed value d by addition to the latter of a certain correction (as ai percentage) equal to 200 gli that electric maintenance of the vibrations can be obtained without the trouble of regulating a trembling arrangement, and without sparking.

The particular form of the apparatus described above is illustrated in the drawing. a is the stand to which is secured the face b ofthe apparatus, carrying the 'sliding scale as described in patent specification No. 1,517,911; at th`e top of the stand is fixed a 7oke d supporting the two vibrating memers e1, e2, actuated by the electromagnets 1, fz," secured to `the stand by means of a racket h and to which the current from the main electric supply is conveyed by the terminals g1, g2g/i1 xs a pin to which the thread being` tested can be momentarilyfsecured ya few turns, after passing it in the hole m1, and i2 is a similar pin to which the comparison thread k is ermanently secured after passing it inthe ole m2. The scale c on a scale n,

positive orv is adjusted as explained inpatent specification No. 1,517,911 and the correction 1s found fixed or slidably mounted behind the standard thread c.

What I claim and desire to Secure by Letters Patent is 1. AnA apparatus for testing textiles comprisinnf an electromagnet adapted to be energized by an alternating current, a single blade of magnetic material dispose-d in t e magnetic eld of said magnet and adapted to be vibrated thereby, the frequency of vibraz tion of said blade being susceptible of variation, and means for suspending the textile to be tested from said blade whereby the vibrations of the blade are imparted to said textile.

2. An apparatus for testing textiles, comprisin a frame, a single vertical blade of magne ic material secured at one end'to said frame, said blade being provided with means for suspending the textile to be tested therefrom, and electrical means for subjecting the blade to the vibrating action of an alternating current, said blade being suiciently thin to be susceptible of variations in its frequency. 1 l

3. An apparatus for testing textiles com- Erising spaced independent ,vibratable memers adapted to im art vibrations to the upper ends respective y of a thread to be tested and ofa thread indicating the corrections due to variations of frequency, means connected with the other end of each thread for exerting a tension on the same, and electrical means operated by a single alternating I current for producing vibration of the v1- .bratable members.

,4. An apparatus for testing textiles comprisin a yoke the downwardly extending legs o which'consists of s members provided at their ower ends with thread receiving openings respectively for enabling the up er ends of a thread to be tested andof a t read indicating the corrections due to variations of frequency threaded through/said openings to be simultaneously vibrated, means connected with the other ends yof the threads for maintaining a tension on the same, and electro-magnets op- Y erated by the same electrical current .for pro- -ducing vibration of the vibratable members.

In testimony whereof I have signed my name to thls specification. n. (p V.msnm Enoulum cUsTAvE umossa'- aced vibratable 

